Watch out with the home purchase. $250,000 would be a $1342.05/month mortgage at 5% interest, and that doesn't include taxes and insurance. While the numbers might work out for you, that's $450 higher than your rent before taxes/insurance. The point is run the numbers carefully, and decide if the house is worth it.
I would contribute to some sort of retirement plan. Even if it's not matched, at least use a roth IRA. You can withdraw contributions whenever you want without penalty, and the earnings are tax-free. The only downside is I'm not sure if you can invest in lower-risk assets within an IRA, so it might not be good for saving a down-payment.
Now on to the expenses:
Is the car line a car payment? What's the car worth? It might make sense to sell it and get something else. If your gas expense is $20/month (assuming $4/gallon gas and 40 mpg), you are driving 200 miles per month. If this is concentrated evenly, that's 6.6 per day. Might be worth selling the car and not buying another, but these are obviously some big assumptions. Essentially, if the 40 mpg assumption is correct, and your numbers are accurate, you're paying $1.75/mile to drive your car.
cable - cut it.
groceries/eating out can be cut, but I'm not sure how since I'm always at $300.
Think about cutting the gym - look for alternatives. Especially when you buy a house, you can start making a home gym.
What are supplements? Like health supplements? These might be good for you, but much of that industry is a scam (could go either way).
Cell phone - should be cut to maybe $100 total, not $100 each.
Insurance - what all insurance does this include? It's a little over twice my car insurance, so it seems high if you get a discount per driver and because you don't seemingly drive much. I'm not sure, but it might be worth shopping around.